docs: def remove_envelop(self, begin, end):
          """
          Removes all intervals completely enveloped in the given range.
  
          Completes in O((r+m)*log n) time, where:
            * n = size of the tree
            * m = number of matches
            * r = size of the search range
          """
          hitlist = self.envelop(begin, end)
          for iv in hitlist:
              self.remove(iv)